"I'm very, very shy. I'm shy to sing anyway," she told Maria. "I'm not the person that will get up and sing karaoke, and so when I sing I have to be in character. And at home, I love listening…Keith has a beautiful voice. He writes music, so there's music in our home. And that's a lovely thing to be able to say that."

Maria also had Nicole clear up a recent quote from the 42-year-old actress that raised a few eyebrows.

The actress told British GQ in its December issue, "I've explored obsession. I've explored loss and love in terms of being in a grief-stricken place, I've explored strange sexual fetish stuff… I've explored the mundane aspect of marriage, and monogamy."

But according to Nicole, the quote was related to her work on the big screen and not what goes on behind closed doors.

"That's what I said in relation to my work. They left that part out," she explained. "In terms of my work, yeah, I'm interested in exploring love, and so that comes in all different forms. And that's what I want to do in terms of my private life, I'd never reveal what I've explored in my private life."

And though Nicole remains guarded about her family and personal life – she revealed to Maria that she and Keith are open to the idea of expanding their brood.

"I mean that's not really up to us, [but,] we're open to anything," Nicole said. "So, we'll see what comes our way."